Distinguish between Consideration and Privity of Contract

Saw this in a Contract Law book aur main confused hua, aapke saath toh kaise hoga. Privity of contract woh batata hai ki contract ke terms kisi dusre ke saath nahin bantte, tabhi unka fayda hota hai. Lekin consideration woh kya hai, agar main contract sign karunga toh usse kya fayda milta hai. Consideration woh hai jo kisi ko khatra, liability ya loss hoti hai agar woh contract break karta hai. Toh kya difference hai? Privity mein to koi dusra shaamil nahin hai, lekin consideration woh hai jissey koi dusra affected hota hai.

Please explain clearly, Judicial Services ki zaroorat hai!